Claims
- 1. A catalyst in a fuel cell electrode, said catalyst comprising alternating layers of a first catalyst material containing Pt and a second catalyst material containing at least one suboxide of a second metal which is not Pt, wherein said catalyst demonstrates a pre-peak of CO oxidation occurring at lower potential than that of the Pt CO oxidation peak.
- 2. A catalyst in a fuel cell electrode, said catalyst comprising alternating layers of a first catalyst material containing Pt and a second catalyst material containing at least one suboxide of a second metal which is not Pt, wherein said catalyst demonstrates a pre-shoulder of CO oxidation occurring at lower potential than that of the Pt CO oxidation peak.
- 3. A catalyst in a fuel cell electrode, said catalyst comprising alternating layers of a first catalyst material containing Pt and a second catalyst material containing at least one suboxide of a second metal which is not Pt, wherein said catalyst demonstrates an early onset of CO oxidation.
- 4. The catalyst according to claim 1 wherein said suboxide of a second metal has the formula MOx, wherein second metal M has one or more stoichiometric oxidation states MOn where n is one or more positive rational numbers, wherein x is not equal to any n and x varies from any n by 5% or more.
- 5. The catalyst according to claim 2 wherein said suboxide of a second metal has the formula MOx, wherein second metal M has one or more stoichiometric oxidation states MOn where n is one or more positive rational numbers, wherein x is not equal to any n and x varies from any n by 5% or more.
- 6. The catalyst according to claim 3 wherein said suboxide of a second metal has the formula MOx, wherein second metal M has one or more stoichiometric oxidation states MOn where n is one or more positive rational numbers, wherein x is not equal to any n and x varies from any n by 5% or more.
- 7. The catalyst according to claim 1 wherein said pre-peak is demonstrated by CO stripping cyclic voltametry performed under conditions of 80° C., ambient pressure and 25 mV/sec scan rate.
- 8. The catalyst according to claim 2 wherein said pre-shoulder is demonstrated by CO stripping cyclic voltametry performed under conditions of 80° C., ambient pressure and 25 mV/sec scan rate.
- 9. The catalyst according to claim 3 wherein said early onset is demonstrated by CO stripping cyclic voltametry performed under conditions of 80° C., ambient pressure and 25 mV/sec scan rate.
- 10. The catalyst according to claim 9 wherein said early onset is demonstrated by a positive slope of the voltametry curve in the region between the point of H2 evolution and a point 140 millivolts more positive than the reference electrode (saturated calomel electrode (SCE)).
- 11. The catalyst according to claim 9 wherein said early onset is demonstrated by a positive slope of the voltametry curve in the region between the point of H2 evolution and a point 110 millivolts more positive than the reference electrode (saturated calomel electrode (SCE)).
- 12. The catalyst according to claim 9 wherein said early onset is demonstrated by a positive slope of the voltametry curve in the region between the point of H2 evolution and a point 80 millivolts more positive than the reference electrode (saturated calomel electrode (SCE)).
- 13. The catalyst according to claim 9 wherein said early onset is demonstrated by a positive slope of the voltametry curve in the region between the point of H2 evolution and a point 50 millivolts more positive than the reference electrode (saturated calomel electrode (SCE)).
- 14. The catalyst according to claim 1 wherein said second metal is selected from the group consisting of Group IIIb metals, Group IVb metals, Group Vb metals, Group VIb metals and Group VIIb metals.
- 15. The catalyst according to claim 2 wherein said second metal is selected from the group consisting of Group IIIb metals, Group IVb metals, Group Vb metals, Group VIb metals and Group VIIb metals.
- 16. The catalyst according to claim 3 wherein said second metal is selected from the group consisting of Group IIIb metals, Group IVb metals, Group Vb metals, Group VIb metals and Group VIIb metals.
- 17. A catalyst in a fuel cell electrode, said catalyst comprising alternating layers of a first catalyst material containing Pt and a second catalyst material containing at least one suboxide of a second metal selected from the group consisting of Group IIIb metals, Group IVb metals, Group Vb metals, Group VIb metals and Group VIIb metals.
- 18. The catalyst according to claim 17 wherein said suboxide of a second metal has the formula MOx, wherein second metal M has one or more stoichiometric oxidation states MOn where n is one or more positive rational numbers, wherein x is not equal to any n and x varies from any n by 5% or more.
- 19. The catalyst according to claim 1 wherein said second metal is selected from the group consisting of Ti, Ta, W and Mo.
- 20. The catalyst according to claim 2 wherein said second metal is selected from the group consisting of Ti, Ta, W and Mo.
- 21. The catalyst according to claim 3 wherein said second metal is selected from the group consisting of Ti, Ta, W and Mo.
- 22. The catalyst according to claim 17 wherein said second metal is selected from the group consisting of Ti, Ta, W and Mo.
- 23. The catalyst of claim 1 wherein said fuel cell electrode is a hydrogen fuel cell electrode.
- 24. The catalyst of claim 2 wherein said fuel cell electrode is a hydrogen fuel cell electrode.
- 25. The catalyst of claim 3 wherein said fuel cell electrode is a hydrogen fuel cell electrode.
- 26. The catalyst of claim 17 wherein said fuel cell electrode is a hydrogen fuel cell electrode.
- 27. A method of making a catalyst according to claim 1 comprising alternating layers of a first catalyst material containing Pt and a second catalyst material containing at least one suboxide of said second metal, comprising alternating steps of deposition of said first catalyst material and deposition of said second catalyst material on a substrate.
- 28. The method of claim 27 wherein said deposition steps comprise methods selected independently from the group consisting of sputter deposition, vapor deposition, cathodic arc deposition, laser ablation and wet chemical methods.
- 29. The method of claim 27 wherein said steps of deposition of said second catalyst material comprise deposition of said second metal in the presence of substoichiometric amounts of oxygen.
- 30. The method of claim 29 wherein said deposition steps comprise the method of sputter deposition.
- 31. A method of making a catalyst according to claim 2 comprising alternating layers of a first catalyst material containing Pt and a second catalyst material containing at least one suboxide of said second metal, comprising alternating steps of deposition of said first catalyst material and deposition of said second catalyst material on a substrate.
- 32. The method of claim 31 wherein said deposition steps comprise methods selected independently from the group consisting of sputter deposition, vapor deposition, cathodic arc deposition, laser ablation and wet chemical methods.
- 33. The method of claim 31 wherein said steps of deposition of said second catalyst material comprise deposition of said second metal in the presence of substoichiometric amounts of oxygen.
- 34. The method of claim 33 wherein said deposition steps comprise the method of sputter deposition.
- 35. A method of making a catalyst according to claim 3 comprising alternating layers of a first catalyst material containing Pt and a second catalyst material containing at least one suboxide of said second metal, comprising alternating steps of deposition of said first catalyst material and deposition of said second catalyst material on a substrate.
- 36. The method of claim 35 wherein said deposition steps comprise methods selected independently from the group consisting of sputter deposition, vapor deposition, cathodic arc deposition, laser ablation and wet chemical methods.
- 37. The method of claim 35 wherein said steps of deposition of said second catalyst material comprise deposition of said second metal in the presence of substoichiometric amounts of oxygen.
- 38. The method of claim 37 wherein said deposition steps comprise the method of sputter deposition.
- 39. A method of making a catalyst according to claim 17 comprising alternating layers of a first catalyst material containing Pt and a second catalyst material containing at least one suboxide of said second metal, comprising alternating steps of deposition of said first catalyst material and deposition of said second catalyst material on a substrate.
- 40. The method of claim 39 wherein said deposition steps comprise methods selected independently from the group consisting of sputter deposition, vapor deposition, cathodic arc deposition, laser ablation and wet chemical methods.
- 41. The method of claim 39 wherein said steps of deposition of said second catalyst material comprise deposition of said second metal in the presence of substoichiometric amounts of oxygen.
- 42. The method of claim 41 wherein said deposition steps comprise the method of sputter deposition.
- 43. A catalyst in a fuel cell electrode, said catalyst comprising alternating layers of a first catalyst material containing Pt a second catalyst material containing at least one suboxide of a second metal selected from the group consisting of Group IIIb metals, Group IVb metals, Group Vb metals, Group VIb metals and Group VIIb metals, and a third catalyst material containing Ru.
- 44. The catalyst according to claim 43 wherein said second metal is selected from the group consisting of Ti, Ta, W and Mo.
- 45. The catalyst according to claim 43 wherein layers of said second catalyst material and said third catalyst material are not adjacent but are interleaved with layers of said first catalyst material.
Parent Case Info
[0001] This application claims the benefit of U.S. Provisional Application No. 60/173,444, filed Dec. 29, 1999.
Provisional Applications (1)
|
Number |
Date |
Country |
|
60173444 |
Dec 1999 |
US |